1. Field
One or more embodiments relate to a method of synthesizing nanowires.
2. Description of the Related Art
Generally, a semiconductor nanowire has uniform properties and may be synthesized to have various thicknesses. In addition, the physical and electrical properties of a semiconductor nanowire may be varied by modifying a surface thereof. Since a semiconductor nanowire may function as a conductive line for electrically connecting nanodevices, research has been conducted on semiconductor nanowires for application in optical nanodevices, electronic nanodevices and nanosensors.
A significant amount of research has been conducted on silicon (Si) nanowires and applications thereof. However, due to the property limitations of Si nanowires, germanium (Ge) nanowires have recently received considerable attention. Since a Ge nanowire has a smaller effective carrier mass, higher carrier mobility and smaller band gap energy when compared to a Si nanowire, Ge nanowires are being considered as a channel material to replace Si nanowires in nano-scale metal oxide semiconductor field effect transistors (“MOS FETs”), nano-scale fast switching devices, and other high frequency devices. In addition, a Ge nanowire may be used in photonic signal detection, such as in an ultra-fast integrated optical interconnect, by controlling the bandgap and diameter of the Ge nanowire. It is therefore desirable to have an improved method that provides a Ge nanowire. Thus, to date, active research has been conducted on Ge nanowire synthesis and application of Ge nanolines to various devices.
Generally, a nanowire may be synthesized using a vapor-liquid-solid (“VLS”) growth method. According to the VLS growth method, a nanowire is grown by melting an alloy of a nanowire material and a metal catalyst, and then precipitating a nanowire material from an interface between the melted alloy, which is in a liquid state, and a substrate, which is in a solid state. However, the synthesized nanowire may be contaminated by an impurity from the metal catalyst. The impurity contamination may adversely affect a property of the nanowire and may cause additional problems when the nanowire is applied in industrial use. It is also therefore desirable to have an improved method that provides a Ge nanowire without impurity contamination.